What does ACL surgery and recovery involve?
ACL surgery is the replacement of a torn anterior cruciate ligament of the knee with a graft or new “ligament”. It is performed arthroscopically using the patella, hamstring, or quadriceps tendon of the patient or from a donor tendon. It is typically an outpatient procedure, meaning that you will return home the day of the surgery.
You can expect to be walking with crutches for approximately 4 weeks after surgery while using a knee immobilizer brace. You will be not be allowed to put any weight into that leg for the first two weeks.
After the first two week, you will slowly begin to put weight through the surgical leg while still using the knee brace for up to 6 weeks after the surgery. The information in this article is for general educational purposes and you should always listen to your surgeon’s advice for your specific situation because your weight bearing precautions may be different than what is mentioned here.
It is important to ice and elevate the knee consistently at the beginning of rehabilitation in order to keep swelling to a minimum to promote healing and return to a normal range of motion and strength.
Physical therapy sessions will begin within a week of the surgery and will continue a few times a week for 3-6 months. It may extend beyond six months if your activities or job require that you rehab to a higher level of function prior to being discharged from physical therapy.
Return to work can range from as little as a few days or up to several months depending on the physical demands of the job.
The length of recovery following an ACL surgery is determined not only by the time it takes for the new ACL to heal but also for you to feel confident with the new ligament in all aspects of your daily activities at home and at work.
ACL healing time:
The healing time for the new ACL is divided into three phases:
1. Early Graft Healing Phase (0 to 4 weeks)
2. roliferative Phase (4 – 12 weeks) - Re-vascularization
3. Ligamentization Phase (12 weeks – 12+ months) - This is when the graft approaches that of a normal ACL
The new ACL will take a long time to fully integrate into the bone and restore strength. It can take the ACL an upwards of 2 years to be most similar to that of a normal, healthy ACL! It is also important to mention that the graft is weakest during the 6-8 week period of healing.
Confidence: Feeling ready to return to work
Your confidence with the new ligament can be tested by your therapist through functional testing of the knee during later stages of your therapy sessions. Physical demands of the job such as squatting, stepping up and down, or standing on one leg can all be evaluated by your therapist’s trained eye. They will be determining if your surgical knee is nearly identical in form when performing these higher level tasks.
It will also be a time that you can test your confidence in a controlled setting while getting feedback from your therapist. Knowing that you are able to perform your job duties as you had prior to your injury can enable you to return to work faster with confidence.
Physical Therapy: a key role in your return to work
Physical therapy plays a major role in your full recovery and return to work after ACL surgery. As mentioned, the therapist is trained to determine if your surgical knee has reached the level of recovery it needs to meet the demands of your job. This does not mean that your knee and new ACL will need to be at 100% recovery before you can return to work.
Those returning to a sport that involves running, cutting, or jumping are cleared to play when the surgical knee can perform functional movements such as squatting and hopping at 90% of the level of the non-surgical or un-injured knee. That number can be much lower if your job requires sitting and moderate walking or standing.
Your physical therapist will also be able to apply manual therapy techniques such as patella (knee cap) mobilizations to ensure that the patella tendon does not shorten thus limiting knee range of motion and resulting in a stiff knee.
One of the most important benefits of working with a physical therapist is to be guided through a proper progression quadriceps and hamstring strengthening exercises. Strong quadriceps (four muscles in the front of the thigh) and hamstrings (three muscles in the back of the thigh) will reduce your risk getting another ACL injury and help you perform your activities safely.
In addition, physical therapists will train you with proprioceptive or balance exercises that will enable you to function with the new ligament in the same way you did prior to the ACL tear. The ACL contains receptors within the ligament that provide information to your brain about the position of your knee.
After the ligament is injured, it becomes challenging to control your knee position due to the damage that occurred to these receptors within the ACL. Therefore, it’s important to train the ACL with balance exercises to avoid excessive arthritis in the knee.
Continuing rehab after return to work
Ending rehabilitation too early may lead to re-injury of the knee because it has not reached adequate strength to perform normal activities of daily living or work duties.
The early phases of PT will deal with decreasing swelling, gaining full range of motion, and developing a return of quadriceps strength. But it is the later stages of healing where exercises will be progressed to include agility, proprioception training, and higher level functional moves.
This later stage of rehab is just as important as beginning stages to ensure a safe but faster return to work. However, even after you have been cleared to return to work, it is important to continue with rehabilitation sessions with your therapist at least once a week or a few times a month to ensure you do not end up with deficits in your strength or range of motion.
In many cases, people still have weak quadriceps and hamstrings after finishing their insurance-based therapy sessions. As mentioned above, functional testing of the knee performed by a physical therapist will objectively measure your strength to identify whether or not you are at risk of tearing your ACL again.
Functional testing should be done before you return to maximum effort at work or playing sports. If you continue to feel weak or do not feel confident then a post-rehab program after physical therapy ends can help you get back to all your occupational and recreational activities with full confidence and strength.
ACL surgery rehabilitation can initially seem like a daunting task, but following the instructions of your surgeon and physical therapist will guide you to a successful recovery.